Interconnecting integrated circuits

Claim 2

An integrated circuit or circuit device having one or more signal outputs characterised in that at least one said output is provided with means for generating an optical or infra-red carrier modulated with an output signal.

Claim 3

An integrated circuit or circuit device including a digital integrated circuit having at least one signal input and a plurality of signal outputs, characterised in that said circuit has means whereby said outputs may be time division multiplexed on to a common output pad, means for converting said multiplexed signal to a modulated optical or infra-red signal for transmission to a remote circuit, and means associated with said input for converting a received optical signal to an electrical input signal.

Claim 4

An integrated circuit or circuit device including a digital integrated circuit having at least one signal input and a plurality of signal outputs, characterised in that said circuit has means whereby said outputs may be time division multiplexed on to a common output pad, means for converting said multiplexed signal to a modulated optical or infra-red signal for transmission to a remote circuit, and means associated with said input for converting a received optical signal to an electrical input signal.

Claim 5

An integrated circuit or circuit assembly, including a digital integrated circuit having a plurality of signal outputs and inputs, switch means whereby said outputs may be coupled selectively to a common output pad in a time division multiplex sequence, clock means for controlling the switch means and a light or infra-red source associated with or mounted on the circuit and coupled to the common output pad whereby, in use, the multiplexed signal is modulated on to an optical or infra-red carrier for transmission to a similar circuit or circuit device, characterised in that said inputs comprise each a photodetector, and wherein, in use, said photodetectors are so controlled by the clock that each photodetector is selectively enabled only for a respective time slot of a multiplexed signal received from a similar circuit or circuit device.

Claim 6

An integrated circuit or circuit assembly, including a digital integrated circuit having a plurality of signal outputs and inputs, switch means whereby said outputs may be coupled selectively to a common output pad in a time division multiplex sequence, clock means for controlling the switch means and a light or infra-red source associated with or mounted on the circuit and coupled to the common output pad whereby, in use, the multiplexed signal is modulated on to an optical or infra-red carrier for transmission to a similar circuit or circuit device, characterised in that said inputs comprise each a photodetector, and wherein, in use, said photodetectors are so controlled by the clock that each photodetector is selectively enabled only for a respective time slot of a multiplexed signal received from a similar circuit or circuit device.

Claim 7

A circuit or circuit device as claimed in claim 2 or 3, characterised in that said light source comprises a laser or a light emitting diode mounted on a common substrate carrier adjacent the circuit.

Claim 8

A circuit or circuit device as claimed in claim 2 or 3, characterised in that said light source is mounted on the circuit and comprises a material lattice matched to the circuit material.

Claim 9

A circuit or circuit device as claimed in claim 5, characterised in that the circuit is of silicon and the light source is a zinc sulphide diode.

Claim 10

A circuit or circuit device as claimed in claim 5, characterised in that the circuit is of gallium arsenide and the light source is a gallium arsenide based diode.

Claim 11

A digital circuit assembly, comprising a plurality of integrated circuits each having means for multiplexing output signals on to an optical or infra-red carrier whereby data is transmitted between circuits, wherein each circuit has clock means whereby synchronisation of all the circuits is achieved, characterised in that each circuit has one or more photodetector inputs, and wherein the inputs of each circuit are controlled by the clock means such that each said input is enabled only for a respective time slot of a received multiplexed signal.

Claim 12

A digital circuit assembly, comprising a plurality of integrated circuits each having means for multiplexing output signals on to an optical or infra-red carrier whereby data is transmitted between circuits, wherein each circuit has clock means whereby synchronisation of all the circuits is achieved, characterised in that each circuit has one or more photodetector inputs, and wherein the inputs of each circuit are controlled by the clock means such that each said input is enabled only for a respective time slot of a received multiplexed signal.

Claim 13

A circuit assembly as claimed in claim 8, and including optical waveguide means whereby the modulated optical infra-red carrier is transmitted between circuits.

Claim 14

A circuit assembly as claimed in claim 9, characterised in that said waveguide comprises a multimode optical fibre.

Claim 15

A circuit assembly as claimed in claim 9 or 10, characterised in that said waveguide has output lens terminations whereby the received optical or infra-red signals are broadcast over each circuit.

Claim 16

A digital circuit assembly as claimed in any one of claims 8 to 11, and comprising a computer or a telephone exchange.

Claim 19

A method as claimed in claim 13, wherein said optical or infra-red carrier is transmitted via a waveguide between the circuits.

Claim 20

A computer or telephone exchange including a plurality of integrated circuits, optical waveguides, whereby data signals are transmitted between said circuits, and means associated with each said circuit for transmitting signals to and receiving signals from one or more said waveguides.

Claim 21

A computer or telephone exchange including a plurality of integrated circuits, optical waveguides, whereby data signals are transmitted between said circuits, and means associated with each said circuit for transmitting signals to and receiving signals from one or more said waveguides.